The research presented in this study has been conducted in an effort to aid in the creation of a biomimetic shell that may be employed in full-scale field experiments to determine the efficacy of mitigation options to limit loggerhead mortality in boat strike incidents. The objectives of this research include the development of experimental testing procedures for the material characterization of the loggerhead carapace, and the design, fabrication, and evaluation of an artificial prototype carapace. A photographic database of wounded sea turtles in Georgia was evaluated in order to determine the primary sources of loggerhead collision injuries and the most common regions of the carapace damaged in boat strike incidents. Skeg impact was found to be the most common source of injury, with a frequency of 44%. In addition, 74% of the sea turtles reviewed sustained injuries to the center third of their carapace length, indicating this region as the most probable impact location. Material testing procedures were developed for evaluating the material properties of the loggerhead carapace. This was followed by the material testing of three loggerhead shells for the purpose of determining localized mechanical properties. Samples were harvested from the shells in a manner designed to identify potential variations in properties due the location and orientation of the coupons within the carapace. Each coupon was subjected to axial tension or three-point bending. Specialized tabs were designed for tension testing in order to accommodate the coupon's irregular geometry and minimize curvature-induced moments. The tensile test results indicated that the longitudinal and transverse properties of the loggerhead carapace were similar. The tensile strength, elongation at failure, and modulus of elasticity were determined to have percent variations of 12.2%, 10.7%, and 10.1% respectively. In contrast, the three-point bending test results indicated that the modulus of rupture and flexural modulus for the transverse samples were approximately four times greater than those of the longitudinal samples. This variation may be attributed to regions of weak tissue running transversely through the carapace. The results of the material testing were utilized in the design of two prototype composite shells. The prototypes were successful in simulating the strain at failure and force per unit width to within 10% of the loggerhead carapace. The resulting procedure may be used to create artificial shells suitable for prototype scale tests in natural environments. In addition, the material testing methods developed for this investigation may offer insight into procedures for evaluating alternate forms of rigid or curved biological specimens.

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: This thesis forms part of the Control Surfaces in Confined Spaces (CoSICS) project conducted at Stellenbosch University. The aim of this project is reduction of control surface actuator footprints on the existing wing structures of commercial airliners such as the Airbus A320 and A330. This is achieved by reducing control surface hinge moments through the application of trailing edge tabs. This results in smaller actuator requirements. The first tier of the project focussed on the geometric optimisation of the tab applied to an aileron. This thesis focusses on the development of dynamic control of the aileron through either tab-only or concurrent tab and aileron actuation. In the effort to develop dynamic control, a fully coupled generalised dynamic model of the tab and aileron is derived and presented. Through linearisation of this model, linear controllers are developed. Two distinctly different controllers are presented; the first controller makes use of classical methods for control of the tab-only actuated aileron and the second controller makes use of modern control techniques such as full state feedback to facilitate controlled concurrent tab and aileron actuation. Each proposed controller is evaluated in terms of dynamic performance, robustness, disturbance rejection and noise immunity. Based on the controller development, a summary of dynamic actuator requirements is given. Practical verification of the model and the controller performance is then undertaken. The development of the necessary hardware and software is also presented. The concept of aileron control through tab-only actuation and concurrent tab and aileron actuation is then validated. Conclusion are then drawn about the accuracy of the theoretical model and the practical performance of the controllers. The thesis is concluded with recommendations for future work to increase the fidelity of the model. Important aspects about the practical implementation of the concept on commercial jetliners are also summarised. / AFRIKAANSE OPSOMMING: Hierdie tesis is deel van die Control Surfaces in Confined Spaces1 projek by Stellenbosch Universiteit. Die doel van hierdie projek behels die verkleining van die aktueerder spasie en ondersteunings struktuur vereistes, op die bestaande vlerk struktuur van kommersiële vliegtuie soos die Airbus A320 en Airbus A330. Dit is bereik deur die vermindering van die beheeroppervlak skarnier se draaimoment met behulp van aerodinamiese hulpvlakke. Kleiner aktueerders word dus benodig. Die eerste stadium van die projek fokus op die geometriese optimisering van die hulpvlak op ’n aileron. Hierdie tesis fokus op die ontwikkeling van dinamiese beheer van die aileron deur middel van hulpvlak aktueering alleenlik of met die gelyktydige aktueering van die hulpvlak en aileron. In die proses van onwikkeling is ’n volgekoppelde veralgemeende dinamiese model van die hulpvlak en aileron afgelei en voorgelê. Deur middel van linearisasie van die model is linieêre beheerders ontwikkel. Tans is twee verskillende beheerders ontwikkel. Die eerste beheerder is gebaseer op die klassieke metodes en maak staat op die aktueering van die hulpvlak alleenlik. Die tweede beheerder maak gebruik van moderne beheer tegnieke soos vol toestand terugvoer om gelyktydige hulpvlak en aileron aktueering te realiseer. Die beheerders is elk geëvalueer in terme van dinamiese gedrag, robuustheid, versteurings verwerping en ruis verwerping. Die beheerstelsel ontwikkeling lei tot ’n opsomming van die dinamiese aktueerder vereistes. Dit word gevolg deur praktiese verifikasie van die model en die beheerstelsel gedrag. ’n Opsomming van die ontwikkeling van nodige hardeware en sagteware word voorgelê. In hierdie proses is die konsep van beide hulpvlak alleenlike aktueering en gelyktydige hulpvlak en aileron aktueering bewys. Gevolgtrekkings word gemaak oor die akkuraatheid van die model en die praktiese gedrag van die beheerders. Die tesis word afgerond met voorstelle vir toekomstige werk wat die model se betroubaarheid kan verbeter. Verder word belangrike punte oor die praktiese aspekte van konsep implementering op kommersiële vliegtuie ook uitgelig.

The main thrust of this thesis is the development of facile synthetic routes for simple boryl anilines and study their structure-property correlations in both solid and solution states and to utilize this information to design functional materials with desired properties such as aggregation induced emission, mechanofluorochromism, and thiol sensors. This thesis contains eight chapters and the contents of each chapter are described below. Chapter 1 The first chapter is an introduction to the theme of the thesis and presents a general review on the present work with emphasis on photophysics of triarylboron based donor-acceptor systems and their applications in various fields. In addition, advances in boron chemistry in the new frontier areas such as aggregation induced emission and mechanochromism are discussed in brief. Chapter 2 The second chapter deals with the general experimental techniques and synthetic procedures utilized in this work. Chapter 3 This chapter describes the rational design and synthesis of triarylborane bearing Unsubstituted amines, namely borylanilines (3.1-3.5). Compounds 3.1-3.4have similar donor and acceptor centres but differ their molecular conformations and also differ in the relative positions of amine moiety (para and meta). Compounds 3.1-3.4 contain one amine group while 3.5 contains two amine moieties. These compounds exhibit fascinating electrostatic intermolecular interactions, N −H- - -π in the crystal structure of 3.1, 3.2 and 3.4 and N −H--N interactions in crystal structure of 3.5. The solution state optical properties of 3.1-3.5 are typical of donor-acceptor (D-A) systems. Interestingly, compounds 3.3 and 3.5 showed unprecedented mechanochromic luminescent properties. Upon grinding, compound 3.3 showed color changes from blue to cyan blue and 3.5 showed intriguing color changes from blue to green and these color changes were found to be reversible. Single crystal X-ray diffraction analysis of 3.5BP (blue emission color crystal) and 3.5GP (green emission color crystal) clearly show that the color changes are due to the difference in their solid state packing. Chapter 4 In chapter 4, the design and facile synthesis of boron based donor-acceptor (D-A) systems such as borylanilines 4.4-4.9 (D= -NH2 for 4.4-4.6 and -NMe2 for compounds 4.7-4.9) are reported. Compounds 4.4, 4.5 and 4.6 contain one, two or three -NH2 moiety(ies), respectively. Compounds 4.7, 4.8 and 4.9 contain one, two or three –NMe2 moiety(ies), respectively. A systematic investigation has been carried out to rationalize the effect of donor-acceptor ratio on the ICT process in borylanilines 4.4-4.9. The aryl spacer between donor amine and acceptor boron is kept the same in all the compounds to avoid the electronic effect of spacer on the ICT characteristics of these compounds. In the case of compounds 4.4-4.6, the increase in the number of donor -NH2 moieties does not affect their absorption profile, while in the case of compounds 4.7-4.9, the absorption spectra are shifted bathochromically with an increase in the number of donor-NMe2 moieties. Photoluminescence (PL) of 4.4-4.6 is significantly blue shifted with an increase in number of –NH2 moieties, while the PL of 4.7-4.9 was slightly blue shifted. The absorption and PL features of 4.4-4.6 are sensitive to the polarity of the solvent medium. In contrast, absorption profiles of 4.7-4.9 are not sensitive to the polarity of the solvent medium. The PL of these compounds is affected by the polarity of the solvent medium. Chapter 5 This chapter deals with triarylboron based fluorescent probes (5.1-5.4) for the selective detection of thiophenols over aliphatic thiols. The probes were constructed by conjugating luminescent borylanilinies with luminescent quencher 2,4-dinitrobenzene sulfonyl (DNBS) moiety. In compound 5.1 and 5.2 the DNBS moiety is positioned at the para position with respect to the triarylborane moiety, while in 5.3 and 5.4 the DNBS moiety(ies) is(are) at the meta position(s). Probes 5.1-5.4 showed selective turn-on fluorescence response towards thiophenol. The fluorescence “off-on” switching mechanism of 5.1-5.4 against thiophenols was fully elucidated by theoretical calculations. Probes 5.1-5.4 are also capable of detecting thiophenols in the intra cellular environments. Chapter 6 Design, facile synthesis and aggregation induced emission properties of a new series of novel triarylboron tethered N-aryl-1,8-naphthalimides (TAB-NPIs) 6.1-6.7 are described in this chapter. Systematic structural perturbation has been used for fine-tuning the optical and morphological properties of TAB- NPIs in both solid as well as in aggregated state. Compounds 6.1-6.7 are weekly luminescent in solutions. In contrast, all compounds (except compound 6.4) are strongly luminescent in the solid state and aggregated state in THF-H2O mixtures. The presence of sterically hindered boryl unit in 6.1-6.7 has endowed these molecules with unique AIE characteristics by preventing co-facial arrangements of NPI moieties. The propeller shape arrangement of TAB moiety in 6.1, 6.2, 6.5, 6.6 and 6.7 effectively prevents the aggregation induced emission quenching (AIEQ) and induce strong emission in the condensed state. In the solid state, compounds 6.1, 6.4, 6.5, and 6.6 generate an interesting supramolecular structure via intermolecular C-H--- and C-H---O interactions. No face to face intermolecular π---π interactions were found in the crystal structures of 6.1, 6.4, 6.5, and 6.6. This precludes the excimer formation which can be detrimental to the radiative process in these molecules. The scanning electron microscopy (SEM) images of as prepared samples of 6.1-6.7 clearly indicate that the morphology of these compounds strongly depends on the molecular conformations and number of naphthalimide moieties in the TAB-NPI conjugates. Chapter 7 This chapter deals with design, synthesis and optical properties of novel dimesitylboryl appended perylenediimides. A simple synthetic strategy has been developed for the construction of novel TAB-PDIs conjugates. These conjugates can be conveniently synthesised by condensation of boryl anilines with perylene tetracarboxylic acid anhydride. The incorporation of TAB moiety enhanced the solubility of perylen bisimides in common organic solvents. The PL quantum yield of both 7.1 and 7.2 strongly depends on the excitation wavelength. Lower Pl efficiency observed for 7.1 and 7.2 upon excitation in the boryl dominated absorption region may be due to the photon induced electron transfer form mesityl units of boryl to perylene bisimide moiety. The morphology as well as emission colours of supramolecular architectures of both 7.1 and 7.2 can be modulated by controlling the concentrations of DCM solutions of these compounds. Both the compounds showed selective fluorogenic response for F-1 and CN-1 anions. The simple synthetic strategy reported in this chapter can be conveniently exploited for the construction of TAB conjugates of semiconducting organic anhydrides. Chapter 8 Novel planar chiral Lewis acids 8.3(SP, SS), 1-phosphino-2-borylferrocenes 8.4(SP) and 2-phosphino-1-borylferrocenes 8.4(RP) have been synthesized from a readily accessible ferrocene sulphinate precursor. Adopting a simple synthetic approach and a single precursor, enantiomerically pure SP and RP isomers have been prepared. It would be worthwhile to investigate the catalytic properties of compounds 8.3(SS), 8.4(SP) and 8.4(RP). It would also be interesting to replace the mesityl groups on boron with other electron deficient groups like pentafluorophenyl and 1,3,5-trifluoromethylphenyl to fine tune the Lewis acidity of boron center and to set-up a general route to enantiomerically pure Planar Chiral Frustrated Lewis Pairs (PCFLP’s).

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: This thesis describes the first project relating to the Control Surfaces in Confined Spaces (CoSICS) project at Stellenbosch University. The aim of CoSICS project is to reduce the size of control surface actuators, and this thesis considers the aileron system of commercial aircraft such as the Airbus A320 and A330. Specifically the project aims to reduce the aileron hinge moment, as this will result in smaller actuators. Possible methods are discussed where aerodynamic forces are used to reduce the aileron hinge moment through the use of a wing-aileron-tab configuration. In order to examine the use of the configuration, first order aerodynamic modelling is performed using two-dimensional thin-aerofoil theory, which is also extended to a basic three-dimensional approximation. To determine the maximum reduction in hinge moment several optimisations are performed where only the tab chord length is varied, both tab and aileron chord lengths are varied, and finally the tab chord length and aileron span are varied. The optimisation methods used, namely the gradient-based sequential quadratic programming (SQP) and a real-encoded genetic algorithm (REGA) are discussed in detail and include general implementations which are then applied to the problem. The optimisations performed are dual-layered where optimal deflection angles are determined as well as the optimal geometry. The results of the optimisation are tested using a roll manoeuvre in a specially developed Simulink simulation environment for this purpose. The study produces results where new hinge moment values are an order of magnitude smaller than those of the old configuration, while maintaining suitable lift and rolling moment coefficients. The optimisation and simulation infrastructure developed in this thesis provides a platform for higher-fidelity models and components being developed in future work to provide higher fidelity results. / AFRIKAANSE OPSOMMING: Hierdie tesis beskryf die eerste projek in die Control Surfaces in Confined Spaces-projek1 (CoSICS-projek) uitgevoer by die Universiteit Stellenbosch. Die doel van die COSICs-projek is om die grootte van beheervlak aktueerders te minimeer en hierdie tesis handel oor die aileron stelsel van kommersiële vliegtuie soos die Airbus A320 en A330. Die doel van hierdie tesisis om die skarnier draaimoment van die aileron te minimeer deur aërodinamiese kragte in te span in ’n vlerk-aileron-hulpvlak konfigurasie. Eerste-orde aërodinamiese modelle is afgelei met behulp van twee-dimensionele dunvlerkteorie en is gebruik om die konfigurasie te analiseer. ’n Eerste orde drie-dimensionele benadering is ook ontwikkel. Om die maksimum vermindering in die skarnier draaimoment te bepaal, is verskeie optimerings uitgevoer waar eers die hulpvlak se koordlengte gevarieer word, daarna beide die aileron en hulp-vlak se koordlengtes en laastens die hulp-vlak se koordlengte en wydte. Die twee optimerings metodes wat gebruik is, nl. ’n sekwensiële kwadratiese programmerings (SKP) tegniek, en ’n reële getal-geënkodeerde genetiese algoritme (RGGA), word bespreek en ontwikkel voor hulle toegepas word op die probleem. Twee-vlak optimerings word uitgevoer waar beide die optimale defleksiehoeke en die optimale geometrie bepaal word. Die resultate van die optimering word daarna getoets deur middel van ’n rol maneuver wat uitgevoer word in ’n Simulink simulasie omgewing wat daarvoor geskep is. Hierdie studie lei tot goeie resultate met skarnier draaimoment waardes ’n ordegrootte kleiner as dié van die vorige stelsel, terwyl goeie waardes van rol-moment en verheffingskrag koëffisiënte behou word. Die optimering en simulasie infrastruktuur wat hier ontwikkel word verskaf ’n platform vir meer akkurate modelle en komponente wat ontwikkel word in toekomstige projekte om meer akkurate resultate te lewer.

Syftet med uppsatsen är att undersöka hur lojala konsumenterna på apoteksmarknaden i Katrineholm är. Eventuella samband mellan kön och lojalitetstyp samt åldersgrupp och lojalitetstyp undersöktes även. För att uppnå syftet genomfördes en kvantitativ undersökning med hjälp av enkäter, där 240 svar samlades in. Konsumenterna delades in i de fyra lojalitetstyper som tas upp i Dick och Basus lojalitetsmodell. Analysen visar att kön inte spelar in i vilken lojalitetstyp individen tillhör. Åldersgruppstillhörighet har dock en signifikant påverkan.

Submitted by Verena Bastos (verena@uefs.br) on 2015-10-02T12:27:57Z No. of bitstreams: 1 Dissertacao_Augusto.pdf: 6330592 bytes, checksum: 7a24562999e9032ffc8a232b0d94049e (MD5) / Made available in DSpace on 2015-10-02T12:27:57Z (GMT). No. of bitstreams: 1 Dissertacao_Augusto.pdf: 6330592 bytes, checksum: 7a24562999e9032ffc8a232b0d94049e (MD5) Previous issue date: 2013-03-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The action of man over nature haphazardly and without adequate planning has led to imbalances in the various terrestrial ecosystems. Thus, it is necessary to formulate strategies to facilitate the balance between human activities and the strengths and weaknesses of environmental systems. One of the strategies used today is the analysis of the use and land cover across sub-basins, an innovation of the technique. Based on that this work has as main objective to analyze changes in land use and land cover in the municipality of Villa Nova, BA, through the use of geotechnology, for the years 1996, 2003 and 2011. The study area is located in the far north of the state of Bahia, Bahia and semi-arid shores of Lake Sobradinho, between the geographical coordinates 41?53' W and 40?39' W and 8?42' S and 09?47' S. The multitemporal analysis for use and land cover featured images of LANDSAT 5 TM, belonging to the municipality for the years 1996, 2003 and 2011, and to reach the purpose were followed methodological procedures that guided this research, structured in four steps: the first step were acquired vector data (GIS database from various sources) and raster data (Landsat and ASTER MDT). The second stage consisted in pre-processing of LANDSAT scenes where applied fixes atmospheric tilt solar and geometric mosaic and clip area. The third step was the digital image processing by performing statistical analysis, preparation of colored compositions, contrast enhancement, image classification and filtering. The fourth step was the post-processing is performed fieldwork for data collection with the help of GPS, these data provided support the calculation of Kappa indices, PABAK and errors of commission and omission, validating the maps with the realization of cross-tabulation between use and land cover, the years of study, and sub-basins extracted from the digital terrain model. The results from this study showed there were changes over time, such as farming areas which decreased missing for other uses. The techniques used allowed the identification of dynamic classes use and land cover in the study region. / A a??o do homem sobre a natureza de forma desorganizada e sem um planejamento adequado vem provocando desequil?brios nos diversos ecossistemas terrestres. Dessa forma, ? necess?rio formular estrat?gias que possibilitem o equil?brio entre a a??o antr?pica e as potencialidades e fragilidades dos sistemas ambientais. Umas das estrat?gias mais utilizadas atualmente ? a an?lise do uso e cobertura das terras atrav?s de sub-bacias hidrogr?ficas, uma inova??o da t?cnica de an?lise. Com base nisso este trabalho tem como objetivo principal analisar as mudan?as no uso e cobertura das terras no munic?pio de Casa Nova, BA, por meio do uso das geotecnologias, no per?odo de 1996, 2003 e 2011. A ?rea de estudo localiza-se no extremo Norte do estado da Bahia, semi?rido baiano e ?s margens do Lago de Sobradinho, entre as coordenadas geogr?ficas 41?53? W e 40?39? W e 8?42? S e 09?47? S. A an?lise multitemporal para o uso e cobertura das terras contou com imagens do sat?lite LANDSAT 5 TM, pertencente ao munic?pio, dos anos de 1996, 2003 e 2011, e para chegar ao objetivo proposto foram seguidos procedimentos metodol?gicos que nortearam essa pesquisa, estruturados em quatro etapas: na primeira etapa foram adquiridos os dados vetoriais (base de dados em SIG de v?rias fontes) e dados raster (LANDSAT e do MDT ASTER). A segunda etapa constituiu no pr?-processamento das cenas do LANDSAT, onde se aplicou corre??es atmosf?rica, inclina??o solar e geom?trica, mosaico e recorte da ?rea. A terceira etapa foi o processamento digital de imagem realizando an?lise estat?stica, elabora??o das composi??es coloridas, realce de contraste, classifica??o da imagem e filtragem. A quarta etapa foi o p?sprocessamento, executou-se o trabalho de campo para coleta de dados com o aux?lio do GPS, estes dados subsidiaram o c?lculo dos ?ndices de Kappa, PABAK e dos erros de Comiss?o e Omiss?o, validando os mapas, com a realiza??o da tabula??o cruzada entre o uso e cobertura das terras, dos anos de estudo, e as sub-bacias extra?das do modelo digital do terreno. Os resultados oriundos dessa pesquisa mostraram houve modifica??es ao longo do tempo, como por exemplo, a agropecu?ria que decresceu perdendo ?reas para outros usos. As t?cnicas usadas possibilitaram a identifica??o da din?mica das classes de uso e cobertura das terras na regi?o de estudo.

In the present work, two phase reacting flow in a single cavity Trapped Vortex Combustor (TVC) is studied at atmospheric conditions. KIVA-3V, numerical program for simulating three dimensional compressible reacting flows with sprays using Lagrangian-Drop Eulerian-fluid procedure is used. The stochastic discrete droplet model is used for simulating the liquid spray. In each computational cell, it is assumed that the volume occupied by the liquid phase is very small. But this assumption of very low liquid volume fraction in a computational cell is violated in the region close to the injection nozzle. This introduces grid dependence in predictions of liquid phase in the region close to the nozzle in droplet collision algorithm, and in momentum coupling between the liquid and the gas phase. Improvements are identified to reduce grid dependence of these algorithms and corresponding changes are made in the standard KIVA-3V models. Pressure swirl injector which produces hollow cone spray is used in the current study along with kerosene as the liquid fuel. Modifications needed for modelling pressure swirl atomiser are implemented. The Taylor Analogy Breakup (TAB) model, the standard model for predicting secondary breakup is improved with modifications required for low pressure injectors. The pressure swirl injector model along with the improvements is validated using experimental data for kerosene spray from the literature. Simulations of two phase reacting flow in a single cavity TVC are performed and the temperature distribution within the combustor is studied. In order to identify an optimum configuration with liquid fuel combustion, the following parameters related to fuel and air such as cavity fuel injection location, cavity air injection location, Sauter Mean Diameter (SMD) of injected fuel droplets, velocity of the fuel injected are studied in detail in order to understand the effect of these parameters on combustion characteristics of a single cavity TVC.

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